The Environmental Protection Agency's new stricter mercury and air toxics rules are making it too expensive for owners of aging coal-fired power plants. This week, FirstEnergy joined a handful of U.S. utilities to decide to close six of its coal-fired power plants rather than install the anti-pollution equipment required to meet the new rules. American Electric Power and Duke Energy also have announced closures of some coal-fired plants.

The six coal plants, located in Ohio, Pennsylvania and Maryland, will be closed by September. These plants, which had a total capacity of 2,689 megawatts, were typically used to meet peak or intermediate power demand. The closing plants generated about 10 percent of the utility's electricity. FirstEnergy has opted to invest in the necessary anti-pollution equipment and upgrades to its remaining coal-fired power plants.

The stricter rules, which were finalized in December, will reduce emissions of mercury, heavy metals and air toxins -- which is a good thing. The new rules could end up reducing emissions even further, as utilities weigh the economics of investing in older, dirtier plants.

Still, the closures will inflict some pain. FirstEnergy's decision affects 529 workers, who will be eligible for severance benefits. Not all of these workers will lose jobs. About one-third of the workers are eligible for retirement. The utility has about 100 job openings in its fossil fuel division, the Akron Beacon Journal reported.

Photo: Craig station in Colorado (not one of the plants slated for closure) Flickr user iagoarchangel, CC 2.0

Kirsten Korosec has written for Technology Review, Marketing News, The Hill, BNET and Bloomberg News. She holds a degree from Northwestern University's Medill School of Journalism. She is based in Tucson, Arizona.
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